dovecot - Sep 2017 - master: Warning: Sent SIGKILL to 511 pop3-login processes

I have a lot of "master: Warning: Sent SIGKILL to 511 pop3-login
processes"
in my log file. Should I worry?

(I'm running # 2.2.32 (dfbe293d4))

Thanks to all,

Luciano.
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